This dissertation comprises three discrete empirical papers, with an introductory essay that evaluates the impact of different federal policies on prescription drug prices, utilization, and spending. Two main databases are used: (a) Medicaid State Drug Utilization Data and (b) the Medical Expenditure Panel Survey (MEPS) data. These two databases are designed to track Medicaid drug utilization and overall medical use and expenditures, respectively. The variables of interest in this dissertation are prescription drug price, prescription drug use and spending, and overall drug expenditures. The objective of the first paper (Chapter 2) is to examine whether oncology drug prices have significantly changed because the Medicaid rebate increased under the Patient Protection and Affordable Care Act (ACA). The analytic sample includes top-selling oncology drugs, both branded and generic, over an 8-year time period. The prices of top-selling oncology drugs in 2006 were followed through 2013 to find the extent to which drug prices have changed while controlling for state fixed-effect, package size, type of manufacturer, brand or generic, and drug strength. Thus, this study examines whether and to what extent oncology drug prices have changed after the increase in the Medicaid rebate under the ACA. The second paper’s objective (Chapter 3) is to study whether Medicare Part D has reduced racial disparities in diabetes drug use, coverage, and spending since its implementation in 2006. The analytic sample includes individuals aged 55 years and older who had diabetes from 2001 to 2010. Although the impact of Medicare Part D has been studied from different perspectives, its impact on racial disparities in drug use, coverage, and expenditures among diabetics has not been studied yet. The third paper (Chapter 4) focuses on the association between closing the Medicare doughnut hole and prescription drug utilization and spending for Medicare Part D beneficiaries with chronic diseases through 2013. The objective of the third paper is to determine whether the provisions of the ACA that close the coverage gap have affected prescription drug utilization and out-of-pocket (OOP) spending among Medicare seniors with Part D coverage.